Il Wednesday 21 November 2007 20:22:46 Joe Conway ha scritto:
> Reg Me Please wrote:
> > The meaning is that an entity called by the value of "item" has a number
> > of properties called by "property" with value "prop_value".
> > So, for a single "item" there can be many different "property" each with
> > its own value.
> >
> > A filter is a list of property values needed to qualify an entity as
> > "good". An entity evaluates as good only when all property values in the
> > filter match the ones associated to an item in t_data.
> >
> > What's missing to me is how to apply a filter to the t_data and get the
> > list of the items that evaluate good.
>
> I haven't played with it myself, but it seems to me that you could do
> this with an inner join of two crosstabs -- one on t_data and one on the
> filters (i.e. you join on the columns of the filter crosstab to the
> matching ones in the t_data crosstab).
>
> Joe
This is a good point.
I just need to avoid doing crosstabs over a very large t_data: I fear it'd
kill the application.
--
Reg me Please
<Non quietis maribus nauta>
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